[Feature] Spoiler for photos and videos

[heitoke]

I have searched the existing feature requests, both open and closed, to make sure this is not a duplicate request.

• Yes

The feature

The essence of the function is to add the ability to apply blur to images and videos, which will work in all sections of the application: in general lists, albums and galleries.

Usage scenario:
The user needs to hide the content from casual eyes, but there is no need to move it to a "Private Folder" (since the content itself is not compromising). This is relevant for situations when the device is used in a public place (for example, in transport) or during a screen demonstration (streaming on Discord), and unauthorized people can see the screen.

Visual implementation:
In the general list (grid), such files are displayed as blurred previews. When you click on a file for full-screen viewing, the image or video is displayed clearly without additional confirmation.

Activation method:
To activate the function, the user just needs to open the context menu for the desired image or video, and select the "Enable spoiler" option.

Platform

• Server
• Web
• Mobile

[flanpowered]

Just the blur would be confusing since Immich already blurs thumbnails of images in the timeline it hasn't finished loading, so I would add a "SPOILER" text or some other informative text over the blur, just like Discord does.

[bo0tzz]

Partial duplicate of #18645.

I don't see us adding another mechanism like this; we already have the locked folder and also the option to archive assets, to hide them without "locking".